Effectiveness of Nonpharmacological Behavioural Interventions in Managing Dental Fear and Anxiety among Children: A Systematic Review and Meta-Analysis

Background: Non-pharmacological behavioural interventions (NPBIs) have been employed by dentists to alleviate dental fear and anxiety (DFA) among preschool and school children. The aim of this systematic review and meta-analysis was to investigate the effectiveness of different NPBIs in reducing DFA among children aged below 12. Method: A comprehensive search was conducted using four electronic databases to identify randomised controlled trials that assess the effectiveness of NPBIs among preschool and school children. Two reviewers independently screened and selected the relevant studies, evaluated the risk of bias, and extracted relevant data for qualitative and quantitative syntheses. Result: A total of 66 articles were included in the study. Except during more invasive dental procedures, the use of distraction techniques was found to result in significantly lower self-rated anxiety, better cooperation, and lower pulse rate compared to the tell–show–do method. However, inconsistent results were reported regarding the efficacy of virtual reality, modelling, visual pedagogies, tell–show–do and other NPBIs in reducing DFA among children. Conclusions: The studies exhibited substantial heterogeneity due to varying age groups, methods of implementing NPBIs, dental treatments performed, and measurement scales employed in the evaluation of DFA.


Introduction
Dental fear and anxiety (DFA) among children are considered amongst the greatest daily challenges faced by general and paediatric dentists [1].Dental fear is a normal emotional reaction to a particular threatening stimulus in a dental situation, while dental anxiety refers to a state of apprehension that something dreadful is going to happen in relation to dental treatment [2].It is a multifactorial and widespread problem affecting all age groups [3].The prevalence of DFA varied considerably according to studies conducted in different countries and among different age groups.For instance, DFA ranged from 4 to 20% among preschool children [4][5][6], 8 to 23% among school children aged 6-12 [5,[7][8][9], 7 to 18% among adolescents [10][11][12], and 14 to 30% in the adult population [10,[13][14][15].
DFA has a significant impact on an individual's pattern of dental service utilisation.It is associated with a delay in seeking dental treatments, and children with DFA are more likely to have more dental caries and poorer oral health [16,17].Therefore, it poses both a problem for dentists and patients [18].Children with dental anxiety tend to only visit the dental clinic when they are experiencing acute pain, which often leads to the need for more traumatic dental procedures.These experiences intensify their fear in subsequent visits [6,[11][12][13].Furthermore, children who have had negative dental experiences perceive stronger pain than those who have had positive experiences, further exacerbating their DFA [19].
Advanced pharmacological interventions, such as general anaesthesia (GA) can be costly and are associated with post-operative complications [20][21][22][23].Treating early childhood caries of a child under GA costs on average over US $2000 [24], and the mortality rate of GA for dentistry is 1 death for every 3.5 million GAs [25].Furthermore, some studies have reported that children who were treated under GA showed caries relapse and required GA reintervention [26][27][28][29].
Different non-pharmacological behavioural interventions (NPBIs) have been used by general dentists and paediatric dentists to instil more positive attitudes of the child towards dental visits.Classical NPBIs include non-verbal communication, tell-show-do, positive reinforcement and distraction [30].Other more novel NPBIs include tell-play-do, mobile dental app, audio-visual distraction, and virtual reality-based distraction [31][32][33][34][35].Most parents and caregivers preferred NPBIs over GA due to several reasons such as lower cost, reduced waiting time and the fear of the possible risks of the pharmacological interventions [36][37][38].To facilitate patient-centred care, alleviate DFA among children and reduce the cost burden of GA for dental treatment, it is necessary to identify more effective NPBIs that can improve DFA among children and foster more positive attitudes.Hence, this systematic review and meta-analysis were conducted to investigate the effectiveness of different NPBI among children below the age of 12.

Materials and Methods
This review was performed and reported according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement [39] (Appendix A).The review protocol was registered in PROSPERO (CRD42023383595).

Identification of Studies (PICO) and Eligibility Criteria
The research question was formulated according to the population, interventioncontrol, and outcomes (PICO) model [40].
For the population, studies included healthy preschool and school children up to 12 years old.Studies that involved children older than 12 years, or children with special needs or physical disabilities were excluded from the analysis.
For interventions, this review included all types of NPBIs that were used for any dental procedures.The interventions included but were not limited to preparatory information, non-verbal communication, voice control, tell-show-do, enhancing control, behaviour shaping and positive reinforcement, modelling, distraction, systemic desensitisation, empathy, motivational interviewing, and hypnosis.
Two types of control groups were included in this review.The first control group being no intervention for behavioural management.The second control group being any other type of NPBIs used in the study as a control group.
This review included randomised and quasi-randomised controlled clinical studies of any duration.Trials with independent treatment arms or crossover studies were both accepted.Only studies published in English were included.Non-randomised interventional studies, surveys, review articles, and case reports were excluded.

Search Strategy
A systematic search was carried out in four electronic databases (Ovid Embase, Ovid Medline, PsycInfo, Web of Science) from inception to 13 October 2022.Broad keywords were used to widen the search (Appendix A).A manual search in grey literature, Google scholar, and by screening of the reference lists of relevant studies was also performed.

Study Selection
Two reviewers (S.S.A and H.C.) independently selected eligible studies based on their titles and abstracts, followed by reading of full-text articles.Cohen's kappa coefficient (k) was used to evaluate the agreements between reviewers.Any disagreement was settled by discussion or consulting the third reviewer (P.P.Y.L.).

Data Extraction
Data extraction of eligible studies was performed by two independent reviewers (S.S.A and H.C.).The extracted information included study characteristics (year of publication, study design, country of studies), age of children, type of non-pharmacological interventions, and type of DFA measurement tools.

Assessment of Risk of Bias of Included Studies
The risk of bias of each included study was assessed independently (S.S.A and H.C) using the Cochrane risk of bias tool (RoB2) [39].This tool included five domains to address different types of bias in (I) the randomisation process, (II) deviation from the intended intervention, (III) missing outcome data, (IV) measurement of the outcome, and (V) selection of the reported result [53].The reviewers independently evaluated each section and classified the risk categories as "low risk of bias", "some concerns", and "high risk of bias".Any disagreements were resolved in consultation with the third reviewer (P.P.Y.L.).

Data Synthesis
The analysis was performed using STATA software version 13.1.The fixed effects model was used for meta-analysis involving fewer than five studies, while the random effects model was used for meta-analysis involving more studies [54].

Subgroup Analysis
Subgroup analyses were carried out to assess the effect of different non-pharmacological interventions with respect to different treatment procedures, subject's age, and study design [40].

Assessment of Heterogeneity
I 2 statistics and Chi square tests were conducted to assess the heterogeneity of the data synthesised [54].The heterogeneity was determined as substantial if I 2 is above 60% or if the p-value in Chi Square test was less than 0.1 [40].

Assessment of Publication Bias
If there were more than ten studies included in the outcome, funnel plots was used for the assessment of publication bias [55].Otherwise, publication bias was not evaluated for the particular outcome.

Assessment of Certainty of Evidence
The overall certainty of evidence were assessed by two independent reviewers (S.S.A., H.C.) using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach to evaluate the certainty of evidence [56].An overall certainty of very low, low, moderate, or high was given, based on the following domains: risk of bias, imprecision, inconsistency, indirectness, and publication bias.The third reviewer was consulted (P.P.Y.L.) in cases of disagreements [56].

Study Selection
A total of 2370 articles were retrieved through 4 databases, with 818 articles removed due to duplication.Screening based on titles and abstracts were performed on 1553 articles.101 full-text articles were further scrutinised, and 66 controlled trials were included in this review (Figure 1).The inter-reviewer agreement was κ = 0.978.
The overall certainty of evidence were assessed by two independent reviewers (S.S.A., H.C.) using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach to evaluate the certainty of evidence [56].An overall certainty of very low, low, moderate, or high was given, based on the following domains: risk of bias, imprecision, inconsistency, indirectness, and publication bias.The third reviewer was consulted (P.P.Y.L.) in cases of disagreements [56].

Study Selection
A total of 2370 articles were retrieved through 4 databases, with 818 articles removed due to duplication.Screening based on titles and abstracts were performed on 1553 articles.101 full-text articles were further scrutinised, and 66 controlled trials were included in this review (Figure 1).The inter-reviewer agreement was κ = 0.978.
In addition to the reduction in dental fear and anxiety, children also exhibited more cooperative behaviours and reported less pain when evaluated with operator-rated behavioural scales (FBRS [50,81]) and self-rated pain scales (WBFS [110], FLACC [50]).However, when compared between studies, considerable heterogeneity was also found (FBRS (I 2 = 83.4%,p = 0.002)) (Appendix B Figure A1).The certainty of evidence was considered very low due to the moderate to high risk of bias of the included studies, inconsistency, and imprecision.
The certainty of evidence of both comparisons was considered very low due to the high risk of bias of the included studies, heterogeneity, and imprecision.

Virtual Reality (VR) vs. Traditional Behaviour Management
When comparing VR versus traditional distraction techniques using self-rated scales, VR showed a significant reduction in child-reported DFA when measured with VPT [93] and WBFS [102,110].No significant reduction in the child's DFA was found when measured with FPS-R [85], FIS [100], and CFSS-DS [102].Heterogeneity was substantial when dental anxiety was measured with WBFS (I 2 = 85.3%, p = 0.009) (Appendix B Figure A2).

Tell-Show-Do vs. no Behavioural Intervention
Two studies reported the dental anxiety level of children when TSD was used compared to no behavioural intervention [75,92].The self-rated anxiety when TSD was used was significantly lower when measured with VPT [75], but not with FIS [75,92] (Appendix B Figure A3).
Inconsistent findings with substantial heterogeneity between studies were also identified when comparing the HR/PR between children receiving TSD and no behavioural interventions.Children receiving TSD had significantly lower HR compared to those receiving no behavioural intervention (I 2 = 87.0%,p = 0.006) (Figure 5).The certainty of evidence was considered very low due to the moderate risk of bias of the included studies, substantial heterogeneity, and imprecision.However, no significant reduction in the child's DFA was found when measured with FLACC [74,82,85] (Appendix B Figure A2).Heterogeneity was substantial when dental anxiety was measured with HR/PR (I 2 = 92.5%,p < 0.001) (Figure 4).

Tell-Show-Do vs. no Behavioural Intervention
Two studies reported the dental anxiety level of children when TSD was used compared to no behavioural intervention [75,92].The self-rated anxiety when TSD was used was significantly lower when measured with VPT [75], but not with FIS [75,92] (Appendix B Figure A3).
Inconsistent findings with substantial heterogeneity between studies were also identified when comparing the HR/PR between children receiving TSD and no behavioural interventions.Children receiving TSD had significantly lower HR compared to those receiving no behavioural intervention (I 2 = 87.0%,p = 0.006) (Figure 5).The certainty of evidence was considered very low due to the moderate risk of bias of the included studies, substantial heterogeneity, and imprecision.

Video Modelling vs. Traditional Behavioural Management
Four studies included in this analysis examined the effectiveness of video modelling compared to traditional behavioural management techniques in reducing DFA among children [77,80,87,88].The studies by Alnamankany et al. (2014) [87] and Alnamankany (2019) [88] demonstrated that watching modelling videos prior to dental treatments resulted in significantly lower self-reported anxiety and pain levels compared to control videos that were irrelevant to dentistry.These outcomes were measured using ACDAS (Abeer Children Dental Anxiety Scale) and VAS, respectively [51,121].Hine et al. (2019) [80] also found a significant reduction in disruptive behaviours when video modelling was utilised, as assessed by a subjective operator-rated scale.However, in contrast to the aforementioned studies, Karekar et al. (2019) [77] found no significant difference in HR between children who received therapeutic storybooks (TSD), live modelling, or video modelling.Interestingly, the TSD group exhibited a lower FIS score [41].

Tell-Show-Do vs. no Behavioural Intervention
Two studies reported the dental anxiety level of children when TSD was used compared to no behavioural intervention [75,92].The self-rated anxiety when TSD was used was significantly lower when measured with VPT [75], but not with FIS [75,92] (Appendix B Figure A3).
Inconsistent findings with substantial heterogeneity between studies were also identified when comparing the HR/PR between children receiving TSD and no behavioural interventions.Children receiving TSD had significantly lower HR compared to those receiving no behavioural intervention (I 2 = 87.0%,p = 0.006) (Figure 5).The certainty of evidence was considered very low due to the moderate risk of bias of the included studies, substantial heterogeneity, and imprecision.

Video Modelling vs. Traditional Behavioural Management
Four studies included in this analysis examined the effectiveness of video modelling compared to traditional behavioural management techniques in reducing DFA among children [77,80,87,88].The studies by Alnamankany et al. (2014) [87] and Alnamankany

Visual Pedagogy vs. No Visual Pedagogy
When comparing the use of pictorial cues to verbal reinforcement without visual cues, no significant difference was detected in children's anxiety when measured with CFSS-DS and VPT during dental examinations (MD: −0.22, 95% CI: −0.53, 0.10; p = 0.185) [69,95] and dental restorative procedures (MD: −0.25, 95% CI: −0.53, 0.02; p = 0.067) [69,78,95].Heterogeneity was substantial during dental examinations (I 2 = 46.9%,p = 0.170) and restorative procedures (I 2 = 81.2%,p = 0.005) (Figure 6).The overall certainty of evidence regarding the effectiveness of visual pedagogy was very low due to the potential risk of bias of the included studies, considerable heterogeneity, and imprecision.(2019) [88] demonstrated that watching modelling videos prior to dental treatments resulted in significantly lower self-reported anxiety and pain levels compared to control videos that were irrelevant to dentistry.These outcomes were measured using ACDAS (Abeer Children Dental Anxiety Scale) and VAS, respectively [51,121].Hine et al. (2019) [80] also found a significant reduction in disruptive behaviours when video modelling was utilised, as assessed by a subjective operator-rated scale.However, in contrast to the aforementioned studies, Karekar et al. (2019) [77] found no significant difference in HR between children who received therapeutic storybooks (TSD), live modelling, or video modelling.Interestingly, the TSD group exhibited a lower FIS score [41].

Discussion
Most of the included studies consistently reported a reduction in DFA and improved behavior in children when distraction techniques were employed, as compared to TSD [50,75,81,92,109,110].Distraction techniques are considered safe and cost-effective procedures that enhance the overall experience for patients undergoing invasive and painful

Discussion
Most of the included studies consistently reported a reduction in DFA and improved behavior in children when distraction techniques were employed, as compared to TSD [50,75,81,92,109,110].Distraction techniques are considered safe and cost-effective procedures that enhance the overall experience for patients undergoing invasive and painful medical and dental procedures [122][123][124].These techniques involve strategies aimed at diverting the patient's attention away from unpleasant procedures [125].However, the studies reviewed exhibited significant inconsistencies.These inconsistencies could potentially be attributed to the wide range of distraction techniques utilised, such as toys, lavender fragrance, music, stories, and videos.It is important to note that an ideal distractor should achieve an optimal level of engagement by incorporating visual, auditory, and kinaesthetic sensory modalities.Additionally, it should elicit an active emotional response from the patient, directing their focus towards the virtual environment and minimising their awareness of the dental setting [126].
In this review, VR was evaluated as a distinct intervention, and the results regarding its effects on DFA in children were inconsistent.VR can be described as a computer-generated three-dimensional (3D) environment that immerses the user in a multisensory experience, temporarily transporting them away from the real world [127].It has gained popularity in both the medical and dental fields [128].Nine studies reported reduced DFA, pain, and HR/PR with the use of VR [72, 74,82,85,93,100,102,109,110].VR provides an immersive visual experience through occlusive headsets, effectively blocking out real-world visual and auditory stimuli.This immersive nature of VR might help alleviate anxiety, pain, and HR in children [86].However, wearing a large VR headset over the face could also lead to a reduction in the visual field, causing a loss of control and potentially exacerbating children's anxiety [89].
Inconsistencies were observed in the effectiveness of modelling and visual pedagogies.One possible explanation for these inconsistencies is the wide variation in the age range of participants across the different studies.The comprehension and enactment of desired behaviours taught through modelling and visual pedagogies are heavily influenced by the cognitive abilities of children, which may be less developed in the younger age groups.Additionally, the cognitive function of children, which improves with age, can also impact their behaviours in an unfamiliar dental setting [129].Therefore, age emerges as a significant confounding factor when evaluating the effectiveness of NPBIs.
There are other NPBIs available, including protective stabilisation techniques like the hand-over-mouth exercise and Papoose board.The choice and acceptance of various behaviour management strategies are greatly influenced by various factors such as culture, parenting style, legal obligation, and the urgency of dental needs.For instance, in the United States, protective stabilisation is commonly used for uncooperative children requiring dental treatment [130].Yet, in the United Kingdom, it is only employed by experienced clinicians under very specific circumstances [131].
Advancements in paediatric dentistry have introduced newer NPBIs such as animalassisted therapy (AAT), which is a noninvasive intervention that involves a specially qualified animal as an integral part of the treatment process.One included randomised controlled trial found AAT to be an effective behaviour management strategy for the current generation of children [114].However as it is a relatively new area for scientific research; more randomised controlled trials are needed to establish specific guidelines for AAT.
Another significant confounding factor is the type of treatment administered.Invasive procedures that cause more pain are more likely to result in higher levels of DFA among children [132].Although this review conducted subgroup analyses based on the interventions employed, the limited number of studies found prevented a comprehensive evaluation of the true effects of NPBIs.Therefore, the influence of treatment type on the effectiveness of NPBIs in reducing DFA could not be fully assessed.
Self-rated scales are commonly used to assess sensations and emotions such as DFA and pain, but their reliability may be compromised when used with children.While many scales employ Likert scales to enhance children's understanding, these measurements still necessitate a significant level of cognitive flexibility.Children must be able to shift their attention between different options, compare and differentiate choices, and retain and consolidate information before selecting the most appropriate response.Young children below the age of four are particularly susceptible to middle bias, as they tend to choose the faces at the endpoints rather than those in between [133].
Many of the included studies also employed indirect methods, such as observing children's behaviours and measuring their pulse rate to assess DFA.Children experiencing higher levels of DFA often exhibit more uncooperative behaviours [134].However, it is important to note that the reluctance of these children to undergo treatments may stem from other psychological and environmental factors other than DFA [135,136].It is worth mentioning that the assessment of behaviours are mostly rated by the operator, which introduces the risk of outcome assessor bias, as operators may not blinded to the specific NPBI being used.On the other hand, physiological responses like heart rate and SpO2 provide more objective measures of evaluating DFA [52,137].However, the equipment or measures used in these studies may not be sensitive enough to detect subtle changes and establish a clear correlation with DFA [138].
The certainty of evidence regarding the effectiveness of all NPBIs evaluated in this review is compromised by several factors.These include significant inconsistencies between studies, potential risk of bias, and small sample size of the included studies.
Future research on NPBIs should prioritise certain improvements to enhance the quality of studies in this field.Firstly, it is crucial to conduct more high-quality randomised controlled trials (RCTs) with standardised protocols for implementing NPBIs.This will ensure consistency and comparability across studies, allowing for more reliable conclusions to be drawn.Furthermore, in terms of outcome assessment and dental anxiety measurement, it is recommended to utilise physiological measurements such as heart rate (HR) and pulse rate (PR).These objective measures provide a fair and unbiased assessment of outcomes, thus enhancing the validity of the findings.Incorporating these physiological measures alongside self-reported measures can provide a more comprehensive evaluation of the impact of NPBIs on dental anxiety.Lastly, future studies should aim to include larger population sizes to increase the statistical power of the trials.This will enhance the generalisability of the results and allow for more robust conclusions to be made regarding the effectiveness of NPBI interventions.By addressing these improvements, future research on NPBIs can contribute valuable insights and further enhance our understanding of its efficacy.These enhancements will ultimately lead to more evidence-based recommendations and improved dental care practices.
This systematic review and meta-analysis followed the guidelines outlined in the Cochrane Handbook for Systematic Reviews [40] and the PRISMA guidelines for reporting [39].The study's eligibility and risk of bias were assessed independently, and subgroup analyses were conducted based on self-and operator-rating scales, as well as intervention types, which are noteworthy strengths of this review.However, one limitation is the possibility of excluding relevant non-English articles, although the impact of this exclusion on the findings may not be significant [139].

Conclusions
The use of distraction techniques led to significantly lower self-rated anxiety, better cooperation, and lower pulse rate in comparison to the tell-show-do method, except during more invasive dental procedures.There were inconsistent results reported regarding the efficacy of virtual reality, modelling, visual pedagogies, tell-show-do and other NPBIs in reducing DFA among children.The studies exhibited substantial heterogeneity due to varying age groups, methods of implementing NPBIs, dental treatments performed, and measurement scales employed in the evaluation of DFA.(review or systematic review or literature review or meta-analysis or case report or case series).mp.[mp = title, book title, abstract, original title, name of substance word, subject heading word, floating sub-heading word, keyword heading word, organism supplementary concept word, protocol supplementary concept word, rare disease supplementary concept word, unique identifier, synonyms] 6.
("animals" or "not humans").mp.[mp = title, book title, abstract, original title, name of substance word, subject heading word, floating sub-heading word, keyword heading word, organism supplementary concept word, protocol supplementary concept word, rare disease supplementary concept word, unique identifier, synonyms] 7.

Figure 1 .
Figure 1.PRISMA flowchart of the current meta-evaluation.

Figure 1 .
Figure 1.PRISMA flowchart of the current meta-evaluation.

Figure 2 .
Figure 2. Assessment of risk of bias using ROB2: A revised Cochrane risk of bias for randomized trials.

Figure 6 .
Figure 6.Forest plot comparison between VP vs. no VP.

Figure 6 .
Figure 6.Forest plot comparison between VP vs. no VP.

(
Behavior* or conditioning or cognitive or cope or coping or Desensiti* or Exposure or flooding or hypno* or distract* or picture* or reapprais* or Mindfulness or Meditation or nonpharmacologic* or non-pharmacologic* or relax* or breath* or music* or audi* or visual* or odor* or smell* or reinforce* or tell show do or tell-show-do or model* or muscle* or biofeedback).mp.
pediatric OR preschool OR child*) AND (dental caries/OR "early childhood caries") AND (Behavior* OR conditioning OR cognitive OR cope OR coping OR Desensiti* OR Exposure OR flooding OR hypno* OR distract* OR reapprais* OR Mindfulness OR Meditation OR nonpharmacologic* OR non-pharmacologic* OR relax* OR breath* OR music* OR audi* OR visual* OR odor* OR smell* OR reinforce* OR "tell show do" OR "tell-show-do" OR model* OR muscle* OR "virtual reality" OR "biofeedback") AND (stress* OR anxi* OR fear* OR phobi* OR pain* OR emotion*) Web of Science Date of search: 7 September 2022 Search results: 695 1. Title = (pediatric or preschool or child* or child* or infant*) 2. AND Title = (dental caries OR carie* OR carious OR DMF) 3. AND Title = (Behavior* OR conditioning OR cognitive OR cope OR coping OR Desensiti* OR Exposure OR flooding OR hypno* OR distract* OR reapprais* OR Mindfulness OR Meditation OR nonpharmacologic* OR non-pharmacologic* OR relax* OR breath* OR music* OR audi* OR visual* OR odor* OR smell* OR reinforce* OR "tell show do" OR "tell-show-do" OR model* OR muscle* OR "virtual reality" OR "biofeedback") 4. AND Title = (stress* OR anxi* OR fear* OR phobi* OR pain* OR emotion* OR fear* OR phobi* OR pain* OR emotion*) 5.

Figure A2 .
Figure A2.Forest plot comparison between VR and traditional behavioural methods.Figure A2.Forest plot comparison between VR and traditional behavioural methods.

Figure A2 .
Figure A2.Forest plot comparison between VR and traditional behavioural methods.Figure A2.Forest plot comparison between VR and traditional behavioural methods.

Figure A2 .
Figure A2.Forest plot comparison between VR and traditional behavioural methods.

Figure A3 .
Figure A3.Forest plot comparison between TSD and no treatment.

Figure A3 .
Figure A3.Forest plot comparison between TSD and no treatment.

Table 1 .
Characteristics of included studies.

4
Dental care or dental treatment or dentistry or oral health 5 review OR systematic review OR literature review OR meta-analysis OR case report OR case series 6 (animals or "not humans").mp.[mp = title, abstract, heading word, drug trade name, original title, device manufacturer, drug manufacturer, device trade name, keyword heading word, floating subheading word, candidate term word] preschool or child*).mp.[mp = title, book title, abstract, original title, name of substance word, subject heading word, floating sub-heading word, keyword heading word, organism supplementary concept word, protocol supplementary concept word, rare disease supplementary concept word, unique identifier, synonyms] 2. dental caries/ 3. (Behavior* or conditioning or cognitive or cope or coping or Desensiti* or Exposure or flooding or hypno* or distract* or reapprais* or Mindfulness or Meditation or nonpharmacologic* or non-pharmacologic* or relax* or breath* or music* or audi* or visual* or odor* or smell* or reinforce* or tell show do or tell-show-do or model* or muscle* or biofeedback or virtual reality).mp.[mp = title, book title, abstract, original title, name of substance word, subject heading word, floating sub-heading word, keyword heading word, organism supplementary concept word, protocol supplementary concept word, rare disease supplementary concept word, unique identifier, synonyms] 4. (stress* or anxi* or fear* or phobi* or pain* or emotion*).mp.[mp = title, book title, abstract, original title, name of substance word, subject heading word, floating subheading word, keyword heading word, organism supplementary concept word, protocol supplementary concept word, rare disease supplementary concept word, unique identifier, synonyms] 5.